Training the inspiratory muscles improves running performance when carrying a 25 kg thoracic load in a backpack

Load carriage (LC) exercise in physically demanding occupations is typically characterised by periods of low-intensity steady-state exercise and short duration, high-intensity exercise while carrying an external mass in a backpack; this form of exercise is also known as LC exercise. This induces inspiratory muscle fatigue and reduces whole-body performance. Accordingly we investigated the effect of inspiratory muscle training (IMT, 50% maximal inspiratory muscle pressure (P_Imax) twice daily for six week) upon running time-trial performance with thoracic LC. Nineteen healthy males formed a pressure threshold IMT (n?=?10) or placebo control group (PLA; n?=?9) and performed 60?min LC exercise (6.5?km?h^–1) followed by a 2.4?km running time trial (LC_TT) either side of a double-blind six week intervention. Prior to the intervention, P_Imax was reduced relative to baseline, post-LC and post-LC_TT in both groups (pooled data: 13?±?7% and 16?±?8%, respectively, p?P_Imax increased +31% (p?TT (+18%, p?P_Imax at each time point was unchanged (13?±?11% and 17?±?9%, respectively, p?>?.05). In IMT only, heart rate and perceptual responses were reduced post-LC (p?p?相似文献   

Examining student-designed games through Suits' theory of games

This paper documents how a unit of student-designed games can create a more meaningful version of physical education (PE) for disengaged students, a version that enhances the educational legitimacy of the subject matter by affording it worth in and of itself rather than being justified for other, extrinsic or instrumental reasons. Furthermore, it seeks to develop new knowledge relating to the conduct of game instruction within PE, by using Suits' theory of games. Drawing on Suits' theory, we develop a conceptual model that is intended to represent the hierarchical processes that occur in gameplay through student-designed games. This model is then tested via examination of the experiences of a cohort of teachers and their year 10 students from a mixed secondary school in the greater London area. From our discussions with the students, it is argued that the key focus of the games that these students were used to playing was the need to ‘play the game well’. By contrast, we suggest that it is possible to provide more meaningful experiences to students if a more philosophically driven and less efficiency-driven approach to games is taken, following Suits' lead more closely. By exploring the loop between and around lusory means, lusory goals and constitutive rules (the aspects of Suits' theory that have been shown to represent student-designed games), students engage with a more meaningful games experience than simply playing the game well. This ‘new’ approach to games may offer counterbalance to the ideological tendencies now emphasized in countries and contexts that celebrate instrumental outcomes of performative PE and sport rather than affording worth in and of itself to the curriculum’s subject matter.     

Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts

Ice hockey body checks involving direct shoulder-to-head contact frequently result in head injury. In the current study, we examined the effect of shoulder pad style on the likelihood of head injury from a shoulder-to-head check. Shoulder-to-head body checks were simulated by swinging a modified Hybrid-III anthropomorphic test device (ATD) with and without shoulder pads into a stationary Hybrid-III ATD at 21 km/h. Tests were conducted with three different styles of shoulder pads (traditional, integrated and tethered) and without shoulder pads for the purpose of control. Head response kinematics for the stationary ATD were measured. Compared to the case of no shoulder pads, the three different pad styles significantly (p < 0.05) reduced peak resultant linear head accelerations of the stationary ATD by 35–56%. The integrated shoulder pads reduced linear head accelerations by an additional 18–21% beyond the other two styles of shoulder pads. The data presented here suggest that shoulder pads can be designed to help protect the head of the struck player in a shoulder-to-head check.     

Effects on muscle strength,maximal jump height,flexibility and postural sway after soccer and Zumba exercise among female hospital employees: a 9-month randomised controlled trial

This 9-month randomised controlled workplace physical activity trial investigated the effects of soccer and Zumba exercise, respectively, on muscle strength, maximal jump height, sit-and-reach flexibility and postural sway among female workers. A total of 107 female hospital employees aged 25–63 were cluster-randomised to a soccer group, a Zumba group or a control group. Training was conducted outside working hours as two to three 1-h weekly sessions the first 3 months and once a week the last 6 months. Tests were conducted at baseline, after 3 and 9 months. The soccer group improved maximal neck extension strength both after 3 (1.2 kg; P < 0.05) and 9 months (1.7 kg; P < 0.01) compared to the control group. The Zumba group improved maximal trunk extension strength (3.1 kg; P = 0.04) after 3 months, with improvements in postural sway velocity moment (?9.2 mm²/s; P < 0.05) and lower limb lean mass (0.4 kg; P < 0.05) after 9 months. No significant intervention effects were revealed in vertical jump height or sit-and-reach flexibility. The present study indicates that workplace-initiated soccer and Zumba exercise may be beneficial for improvement of the neck and trunk strength, which may have preventive effects with regard to future perceived muscle pain in the respective body regions. Furthermore, the Zumba group revealed positive effects on lower limb lean mass and postural sway compared to the control group.     

An ecological analysis of a preschool mastery climate physical education programme

Background: Previous studies of mastery motivational climates within physical education have reported that providing students with opportunities to become self-directed leads to a number of positive outcomes, including skill attainment and increased perceptions of ability. Nonetheless, within all of these studies, there has been no account of the teaching/learning process or the behaviour of the students and teachers within the various interventions.

Purpose: The purpose of this study was to provide a micro-analysis of life in a mastery climate which was grounded in the classroom ecology paradigm.

Participants and setting: The participants in this study were 13 children (11 boys and 2 girls) all aged 4 years at the commencement of the programme. The children were attendees at a day-care centre that serves mostly African-American children from the local community who are environmentally at risk for developmental delay and poor health. The teacher in this study was a faculty member at the university where the programme took place. For 30 minutes each Tuesday and Thursday, the children participated in a programme of motor skill instruction that was based upon the key principles of a mastery-motivational climate. Selected station activities were designed to promote the acquisition of locomotor and object control skills.

Methods: A mixed-methods approach was taken, with data sources including interviews with the teacher, and an analysis of the ecology of the gymnasium using a modified version of the task structure system. Focus was placed upon the task goals, the teacher's accountability strategies, as well as task accomplishment in both the managerial and instructional task systems.

Findings: The key finding from this study was an appreciation of how time is a significant factor in the ways in which children initially responded to and eventually embraced the freedoms afforded to them in a mastery climate. Of particular note, the results show substantial differences in the children's lesson engagement not only across time, but also within lessons themselves. It is hypothesized that as they progressed through the programme, the children not only were more able to identify the demands of the task but were also able to filter out extraneous signals that might promote off-task or inappropriate behaviour.

Conclusions: The design of this study reinforced the value of adopting an ecological analysis of life in a mastery climate. Further, the results of the study showed the value of examining young children's engagement over a lengthy intervention. While such climates are expected to have lower levels of engagement and higher levels of off-task behaviour than more teacher-directed formats, by the end of the study the children were able to achieve levels of appropriate task engagement above 80% of lesson time.     

Development of a performance assessment task and rubric to measure prospective secondary school mathematics teachers’ pedagogical content knowledge and skills

The purpose of this paper is to share a performance assessment task and rubric designed to assess secondary school mathematics preservice teachers’ pedagogical content knowledge and skills. The assessment task and rubric were developed in collaboration with five education faculty, four arts and sciences faculty, and four high school teachers over a period of one year. Over this period, the group met more than 15 times and designed an assessment task and rubric to measure secondary school preservice teachers’ pedagogical content knowledge and skills. The assessment task and rubric were piloted at the end of the year and extensively revised using the pilot data. The redesigned task and rubric were successfully carried out in the second and subsequent years. Other teacher education programs can benefit from this assessment of teacher candidates’ pedagogical content knowledge and skills.     

Labour perspectives on the new politics of skill and competency formation: International reflections

Skill/competency approaches to workplace-based policy seek to assess and train for discrete individual competencies with the goal of increasing employability and productivity. These approaches have become increasingly prominent across a range of advanced capitalist countries. A substantial critique has emerged over this same period regarding issues of instrumentality and social control, as well as the failure of skill/compentancy approaches to articulate a meaningful understanding of human learning capacities. In this article, these critical perspectives are clarified further by a review of contributions to understanding the skill/competence question emerging from sociology of work literature. Building from these critiques, this article outlines recent experiences with and perspectives on skill/competency frameworks amongst different national labour movements. Included in this outline is a more detailed, comparative analysis of Norway and Canada; here we see the lofty ‘new’, ‘knowledge economy’ rhetoric — in two countries where one might expect to see it blossom in application — brought down to earth by the realities of industrial relations, employer intransigence and intra-labour movement differences. ‘Skill/competence’ proves to be a floating signifier that, amongst both employers and labour, stands as a proxy for ‘power/control’ struggles. Degenerating in this way, from a labour perspective, the new politics of skill/competency formation is seen to have spiraled toward irrelevance in Norway and Canada; awaiting, in both countries, a re-invigoration through attention to changes in the participatory structure of the labour process itself.     

Parental teaching styles in an open-ended teaching-learning environment

The present study extends earlier work on parental teaching style by making the task to be completed less structured, extending parent-child interaction over a 2 week time period, and equalizing the expertise of the parent relative to the child. Additionally, the study examines the effects of parental intrusiveness on a subsequent task. Subjects were 22 Caucasian middle class parent-child dyads. Audiorecordings were taped over a 2-week period while dyads were learning aspects of Logo computer programming. Even in this prolonged nonspecific learning situation, in which parents were encouraged to proceed at the child's pace, parents were overwhelmingly directive. Additionally, children of directive parents performed best on a subsequent generalization task.     

Self‐regulation strategies improve self‐discipline in adolescents: benefits of mental contrasting and implementation intentions

Adolescents struggle with setting and striving for goals that require sustained self‐discipline. Research on adults indicates that goal commitment is enhanced by mental contrasting (MC), a strategy involving the cognitive elaboration of a desired future with relevant obstacles of present reality. Implementation intentions (II), which identify the action one will take when a goal‐relevant opportunity arises, represent a strategy shown to increase goal attainment when commitment is high. This study tests the effect of mental contrasting combined with implementation intentions (MCII) on successful goal implementation in adolescents. Sixty‐six 2nd‐year high school students preparing to take a high‐stakes exam in the fall of their third year were randomly assigned to complete either a 30‐minute written mental contrasting with implementation intentions intervention or a placebo control writing exercise. Students in the intervention condition completed more than 60% more practice questions than did students in the control condition. These findings point to the utility of directly teaching to adolescents mental contrasting with implementation intentions as a self‐regulatory strategy of successful goal pursuit.